Advanced Engineering Physics 2022 Question Paper — Government College…
The 2022 Advanced Engineering Physics previous year question paper (Government College of Engineering and Technology, Jammu), with every question and its marks.
- University: Government College of Engineering and Technology, Jammu
- Subject: Advanced Engineering Physics
- Course: Applied Engineering Physics
- Year: 2022
- Paper: end-term
- Duration: 180 minutes
- Total marks: 100
Instructions
- Attempt five questions in all, selecting at least two questions from each section.
- Each question carries 20 marks.
- Use of Scientific Calculator is allowed.
Questions
SECTION—A
- Q1. (a) Explain the terms: (i) gradient of a scalar field. (ii) divergence of a vector field. Discuss their physical significance giving examples. (12) (b) A light source has a beam power of 50 gigawatts and diameter of 2 mm. Find the peak value of E and B. (8) [20 marks]
- Q2. (a) State and explain spontaneous emission and stimulated emission. Discuss Einstein's co-efficient and derive relation between them. (12) (b) A ruby laser emits 0.1 J pulses of light of wavelength 720 nm. How many minimum numbers of $\text{Cr}^{3+}$ ion is there in ruby? (8) [20 marks]
- Q3. (a) What is Compton effect? Determine expression for Compton shift and Compton wavelength. Is the effect observable with visible light? (12) (b) A wave function given as $\Psi(x)= A \sin \left(\frac{n \pi x}{L}\right) \quad 0 < x < L$ $= 0 \quad \text{outside}$ Find the Normalized wave function. (8) [20 marks]
- Q4. (a) State Schrodinger's wave equation for a particle in a one 1-Dim box with infinite hard walls. State the boundary conditions and solve it to obtained normalized wave function and values of energy for different states of the particle. (12) (b) If $\vec{A}$ and $\vec{B}$ are irrotational, then prove that $\vec{A} \times \vec{B}$ is solenoidal. (8) [20 marks]
SECTION—B
- Q5. (a) Explain drift and diffusion of charge carriers in semiconductors. Derive Einstein's relation for a P-N junction. (12) (b) What is the concentration of holes in Silicon crystals having donor concentration of $1.4 \times 10^{24}/\text{m}^3$ when the intrinsic carrier concentration is $1.4 \times 10^{18}/\text{m}^3$? Find the ratio of electron to hole concentration. (8) [20 marks]
- Q6. (a) Discuss the formation of Newton's rings by reflected light. Describe the experimental arrangement and give necessary theory. Why are Newton's rings circular? (12) (b) In a plane transmission grating the angle of diffraction for second order maxima is $30^\circ$. Calculate the number of lines in one centimetre of the grating surface. $\lambda = 5 \times 10^{-5} \text{ cm}$. (8) [20 marks]
- Q7. (a) Discuss the construction of optical fibre. Find the expression for acceptance angle and numerical aperture in case of optical fibre. (12) (b) An optical fibre has a numerical aperture of 0.2 and a cladding refractive index of 1.59. Determine the acceptance angle for the fibre in water which has a refractive index of 1.33. (8) [20 marks]
- Q8. (a) Differentiate between n-type and p-type semiconductors. Derive an expression for the electron concentration in an intrinsic semiconductor and hence explain the concept of fermi level for an intrinsic semiconductor. (12) (b) Newton's rings are observed in reflected light of wavelength $5.9 \times 10^{-7} \text{ m}$. The diameter of $10^{\text{th}}$ dark ring is $0.5 \text{ cm}$. Find the radius of curvature of the lens and thickness of the air film. (8) [20 marks]